Caryopsis transfer system in an Avena magna Murphy et Terrell × A. longiglumis Dur. amphiploid

Evaluation of the structure of the caryopsis transfer system is presented for an Avena magna × A. longiglumis amphiploid. Each component of the system such as vascular bundle, pigment strand, nucellar projection and ventral aleurone layer varies between the amphiploid and its parental species. The number of xylem vessels present in the caryopsis bundle expressed heterosis-like inheritance. The position of the caryopsis xylem bundle in A. longiglumis shows a lower efficiency in assimilate transport. Some anomalies in the development of the ventral aleurone layer and parenchyma, adjacent to the transfer system, are presented.